The present invention relates to an automatic start controlling apparatus and a detector for detecting engagement of a clutch of an internal combustion engine. Particularly, the present invention pertains to an automatic start controlling apparatus and a clutch engagement detector of an internal combustion engine having a transmission that includes a clutch actuated by a drive source other than the engine when the engine is not running.
Japanese Unexamined Patent Publication No. 9-71138 discloses an economy running system. The system automatically stops the engine when the vehicle stops, for example, at an intersection, and automatically starts the engine by actuating a starter when the vehicle is started. The system includes an automatic transmission that has a clutch.
To quickly start the vehicle after the engine is automatically stopped by the system, the automatic transmission is preferably engaged when the engine is not running. That is, the automatic transmission preferably receives hydraulic pressure regardless of whether the engine is running. The system disclosed in Japanese Unexamined Patent Publication No. 11-147424 has a battery powered electric oil pump, which generates hydraulic pressure and applies the pressure to an automatic transmission. The system disclosed in Japanese Unexamined Patent Publication No. 8-14076 includes an accumulator, which stores hydraulic pressure to maintain a clutch engaged so that the vehicle can be quickly started after an automatic stop procedure.
Even if an economy running system has an electric oil pump or an accumulator, the clutch engagement may be inadequate after the engine is automatically stopped. For example, if air is caught in the oil, if the oil pump is frozen or if a conducting wire is broken, a sufficient hydraulic pressure cannot be generated and sufficient engagement of the clutch cannot be maintained.
If the engagement of the clutch is insufficient after the engine is automatically stopped, the pump of the automatic transmission starts applying sufficient hydraulic pressure to the clutch when the engine is started, which suddenly engages the clutch. The sudden engagement of the clutch creates shock and thus disturbs the driver. Particularly, if the clutch is suddenly engaged after the driver steps on the acceleration pedal, a relatively great shock is created.
Accordingly, it is an objective of the present invention to provide an automatic start controlling apparatus for an internal combustion engine having an automatic transmission that reduces shock when the clutch is engaged. Another objective is to provide a detector that detects the engagement of the clutch without any additional sensor.
To achieve the above objective, the present invention provides an automatic start controlling apparatus for automatically starting an internal combustion engine coupled to a transmission. The transmission has an input shaft connected to the engine, an output shaft, and a clutch located between the input and output shafts. The clutch is engaged to transmit the output torque of the engine from the input shaft to the output shaft. The clutch is actuated by a drive source other than the engine when the engine stops. The automatic start controlling apparatus has a controller. When the engine is automatically started, the controller detects whether the clutch is completely engaged. When the controller judges that the clutch is partially engaged, the controller reduces the output torque of the engine or limits an increase of the output torque.
The present invention also provides an automatic start controlling apparatus for automatically starting an internal combustion engine coupled to a transmission. The transmission has an input shaft connected to the engine, an output shaft, and a clutch located between the input and output shafts. The clutch is engaged to transmit the output torque of the engine from the input shaft to the output shaft. The clutch is actuated by a drive source other than the engine when the engine stops. The automatic start controlling apparatus has a controller. When the engine is automatically started, the controller detects whether the clutch is completely engaged. When the controller detects that the clutch is partially engaged, the controller controls the clutch to gradually and completely engage.
The present invention also provides a detecting apparatus for detecting an engagement state of a clutch. The clutch is included in a transmission coupled to an internal combustion engine. The transmission has an input shaft, which is connected to the engine, and an output shaft. The clutch is located between the input shaft and the output shaft and is engaged to transmit the output torque of the engine from the input shaft to the output shaft. The clutch is actuated by a drive source other than the engine when the engine stops. The detecting apparatus comprises means for determining whether the running state of the engine satisfies a predetermined automatic start condition while the drive source actuates the clutch to engage the clutch, and means for detecting whether the clutch is completely engaged based on the rotation of the input shaft of the transmission when the determining means determines that the condition is satisfied.
The present invention also provides a detecting apparatus for detecting an engagement state of a clutch. The clutch is included in a transmission coupled to an internal combustion engine. The transmission has an input shaft, which is connected to the engine, and an output shaft. The clutch is located between the input shaft and the output shaft and is engaged to transmit the output torque of the engine from the input shaft to the output shaft. The clutch is actuated by a drive source other than the engine when the engine stops. The detecting apparatus comprises means for determining whether the running state of the engine satisfies a predetermined automatic start condition while the drive source actuates the clutch to engage the clutch, and means for detecting whether the clutch is completely engaged based on the rotation speed of the input shaft, the rotation speed of the output shaft and a gear ratio of the transmission when the determining means determines that the condition is satisfied.
The present invention also provides a method for automatically starting an internal combustion engine coupled to a transmission. The transmission has an input shaft connected to the engine, an output shaft, and a clutch located between the input and output shafts. The clutch is engaged to transmit the output torque of the engine from the input shaft to the output shaft. The method comprises actuating the clutch by a drive source other than the engine when the engine stops, detecting whether the clutch is completely engaged when the engine is automatically started, and reducing the output torque of the engine or limiting an increase of the output torque when detecting detects that the clutch is partially engaged.
The present invention also provides a method for automatically starting an internal combustion engine coupled to a transmission. The transmission has an input shaft connected to the engine, an output shaft, and a clutch located between the input and output shafts. The clutch is engaged to transmit the output torque of the engine from the input shaft to the output shaft. The method comprises actuating the clutch by a drive source other than the engine when the engine stops, detecting whether the clutch is completely engaged when the engine is automatically started, and controlling the clutch to gradually and completely engage when the detecting detects that the clutch is partially engaged.
The present invention also provides a detecting method for detecting an engagement state of a clutch, wherein the clutch is included in a transmission coupled to an internal combustion engine. The transmission has an input shaft, which is connected to the engine, and an output shaft. The clutch is located between the input shaft and the output shaft and is engaged to transmit the output torque of the engine from the input shaft to the output shaft. The method comprises actuating the clutch by a drive source that differs from the engine when the engine stops, determining whether the running state of the engine satisfies a predetermined automatic start condition while the drive source actuates the clutch to engage the clutch, and detecting whether the clutch is completely engaged based on the rotation of the input shaft of the transmission when determining that the condition is satisfied.
The present invention also provides a detecting method for detecting an engagement state of a clutch. The clutch is included in a transmission coupled to an internal combustion engine. The transmission has an input shaft, which is connected to the engine, and an output shaft. The clutch is located between the input shaft and the output shaft and is engaged to transmit the output torque of the engine from the input shaft to the output shaft. The method comprises actuating the clutch by a drive source that differs from the engine when the engine stops, determining whether the running state of the engine satisfies a predetermined automatic start condition while the drive source actuates the clutch to engage the clutch, and detecting whether the clutch is completely engaged based on the rotation speed of the input shaft, the rotation speed of the output shaft and a gear ratio of the transmission when determining that the condition is satisfied.